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>mat_inv</H1
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><H2
>Name</H2
>mat_inv&nbsp;--&nbsp;computes the inverse of the input matrix</DIV
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><H2
>Synopsis</H2
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><PRE
CLASS="FUNCSYNOPSISINFO"
>#include &lt;it/linalg.h&gt;
      </PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>mat mat_inv</CODE
>( mat m
        );</CODE
></P
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><H2
>DESCRIPTION</H2
><P
> The function <CODE
CLASS="FUNCTION"
>mat_inv</CODE
> computes the in-place inverse of the matrix <CODE
CLASS="PARAMETER"
>m</CODE
> using LU decomposition. If the matrix is singular, the output is set to NULL, otherwise the output is a pointer to the (modified) input matrix.  </P
><H2
>RETURN VALUE</H2
><P
>    NULL is matrix is singular, non-NULL otherwise
   </P
><H2
>EXAMPLE</H2
><PRE
CLASS="PROGRAMLISTING"
>&#13;#include &lt;linalg.h&gt;

...

mat m1 = mat_new( 3, 3 ); 

m1[0][0] = 1;   m1[0][1] = 5;   m1[0][2] = 2; 
m1[1][0] = 2;   m1[1][1] = 3;   m1[1][2] = 5; 
m1[2][0] = 3;   m1[2][1] = 7;   m1[2][2] = 3; 

mat_inv (m1); 

/*
m1=
[[   -0.897    -0.034     0.655]
 [    0.310    -0.103    -0.034]
 [    0.172     0.276    -0.241]]
*/&#13;</PRE
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